The present invention relates to a cathode ray tube (hereinafter sometimes referred to simply as xe2x80x9cCRTxe2x80x9d) excellent in uniformity in brightness of an image. More particularly, it relates to a functional film which imparts such functions to a CRT and its production process.
It is required for a CRT that the brightness of an image displayed in its screen is uniform.
As a method to make the brightness of an image uniform, (1) a method wherein the transmittance of light of a panel glass is made constant in the plane, and (2) a method wherein, while a transmittance distribution of light is permitted to be present in the panel glass, it is corrected by an intensity distribution of an electron beam, and a distribution is imparted to the emission intensity of a phosphor, have been proposed.
However, as the former method (1), it has been attempted to overcome the difference in transmittance of light due to the thickness of glass by improving the transmittance of light of the glass base, however, the significant difference in thickness between the center portion and the peripheral portion of the panel glass, corresponding to flattening of the panel glass in recent years, can not adequately be overcome.
The latter method (2) has a technical limit such that when a panel glass has a significant difference in transmittance of light, such as a difference in transmittance of light of at least 10%, it can not cope therewith, and it has been difficult to achieve uniformity in brightness over the entire plane of the panel glass.
Further, as another related technology, JP-A-61-185852 discloses a method wherein the total glass thickness within the display area is made constant by attaching a front panel made of glass and provided with a thickness variation to the front surface of the panel glass by a resin. However, this method has had a problem that the weight of CRT increases. Further, a requirement for antireflection on the surface of the panel glass is increasing in recent years.
The present invention has been made to overcome such problems, and it is an object of the present invention to provide a functional laminated film which can prevent reflection on the surface, and which can make the brightness of an image uniform, particularly regarding a CRT corresponding to flattening in recent years, and its production process.
The above object can be overcome by the following means. That is:
(1) A functional laminated film comprising a substrate film, an antireflection layer provided on one side of the substrate film, a colorant layer having a color density distribution provided on the other side of said substrate film, and an adhesive layer laminated on said colorant layer side.
(2) A functional laminated film comprising a substrate film, an antireflection layer provided on one side of the substrate film, and a colored adhesive layer having a color density distribution provided on the other side of said substrate film.
(3) A process for producing the functional laminated film as defined in the above (1), which comprises providing an antireflection layer on one side of a substrate film, providing a colorant layer having a uniform color density on the other side of said substrate film, irradiating said colorant layer with ultraviolet rays by means of a mask having a distribution of the transmission amount of ultraviolet rays to form a colorant layer having a color density distribution, and laminating an adhesive layer on said colorant layer.
(4) A process for producing the functional laminated film as defined in the above (1), which comprises providing an antireflection layer on one side of a substrate film, providing a colorant layer having a uniform color density on the other side of said substrate film, laminating an adhesive layer on said colorant layer, and irradiating said colorant layer with ultraviolet rays by means of a mask having a distribution of the transmission amount of ultraviolet rays to form a colorant layer having a color density distribution.
(5) A process for producing the functional laminated film as defined in the above (2), which comprises providing an antireflection layer on one side of a substrate film, providing a colored adhesive layer having a uniform color density on the other side of said substrate film, and irradiating said colored adhesive layer with ultraviolet rays by means of a mask having a distribution of the transmission amount of ultraviolet rays to form a colored adhesive layer having a color density distribution.
(6) A process for producing the functional laminated film as defined in the above (2), which comprises providing an antireflection layer on one side of a substrate film, providing a colored adhesive layer having a uniform color density on the other side of said substrate film, laminating a release film on said colored adhesive layer, and then irradiating said colored adhesive layer with ultraviolet rays by means of a mask having a distribution of the transmission amount of ultraviolet rays to form a colored adhesive layer having a color density distribution.
(7) A CRT comprising the functional laminated film as defined in the above (1) or (2) attached thereto.